#include <stdio.h>
void pay_amout(int dollars, int *twenties, int *tens, int *fives, int *ones);
int main(void)
{
    printf("Enter a dollar amount: ");
    int amount;
    scanf("%d", &amount);
    int a20, a10, a5, a1;
    pay_amout(amount, &a20, &a10, &a5, &a1);
    printf("$20 bills: %d\n", a20);
    printf("$10 bills: %d\n", a10);
    printf(" $5 bills: %d\n", a5);
    printf(" $1 bills: %d\n", a1);
    return 0;
}
void pay_amout(int dollars, int *twenties, int *tens, int *fives, int *ones) {
    *twenties = dollars / 20;
    dollars = dollars % 20;
    *tens = dollars / 10;
    dollars = dollars % 10;
    *fives = dollars / 5;
    dollars = dollars % 5;
    *ones = dollars;
}